Grooving machine



June 7, 1955 c. l.. oLsoN GRoovING MACHINE 2 shees-sheet 1 Filed May 7,1953 United States Patent O GRoovlNG MACHINE Clarence Leroy Olson, SanFrancisco, Calif.

Application May 7, 1953, Serial No. 353,471

Claims. (Cl. 51176) The invention relates to devices for forming groovesin floors, steps, stair treads, and other walking surfaces of variousmaterials, for the inclusion in such grooves of ornamental and/ornon-slip materials and compounds.

An object of the present invention is to provide a grooving machine, ofthe character described, which will be readily portable, self-containedand easily positionable upon and movable over the surface to be grooved,such as a step or other walking surface, and which will rapidly andcleanly cut a uniform groove at precise positions desired for insertionof a friction or an ornamental material in the groove to provide anon-slip or decorative area on the step or walking surface.

Another object of the present invention is to provide a machine of thecharacter above, which may be easily and precisely adjusted at the endof each pass along the surface to be grooved to increase the depth ofcut by the desired increment, and in which the groove cutting means maybe rapidly removed to a safeguarded, protected position completelyenclosed within the machine when the grooves are completed and themachine is ready to be moved on to the next step or to remove it fromthe job.

A further object of the present invention is to provide a machine of thecharacter described having an irnproved casing construction providing,for the cutting means, an enclosed work chamber which is verticallyextensible to afford the adjustments above noted and which may beconveniently evacuated by suction means'so as to remove dust and gritgenerated by the cutting means, in the interests of providing increasedcomfort and good, clean breathing air for the operator and cleanlinessof the premises.

Yet another object of the present invention is to provide a machine, ofthe character described, which combines sturdy and simply formedmechanisms in a unitary assembly of high strength and rigidity and oflightness of weight for easy portability.

The invention possesses other objects and features of advantage, some ofwhich, with the foregoing, will be set forth in the followingdescriptions of the preferred form of the invention which is illustratedin the drawings accompanying and forming part of the specification. Itis to be understood, however, that variations in the showing made by thesaid drawings and description may be adopted within the scope of theinvention as set forth in the claims.

Referring to said drawings:

Figure 1 is a top plan view of a grooving machine constructed inaccordance with the present invention.

Figure 2 is a side elevational viewof the machine of Figure 1 withportions broken away and shown in section to reveal the internalstructure of the machine.

Figure 3 is an end elevational view of the machine.

Figure 4 is a' plan sectional view of the machine taken substantially onthe plane of line 4 4 of Figure 3.

The grooving machine of the present invention, and as illustrated in theaccompanying drawings, consists "ice briey of a body or casing 11adapted for positioning on and movement over the surface to be grooved(here step 17) and composed of relatively movable upper and lowersections 12 and 13 cooperating to dene a vertically expansible workchamber 14 opening at its bottom to the step 17 and in which ispositioned a rotary grooving means 16, carried by the upper section 12for movement therewith upon relative displacement of the sections so asto extend through the bottom of the casing and into cutting engagementwith the step 17 being grooved, the relative displacement of thesections being effected by a manually operable means 1S mounted on thecasing. ln accordance with the present invention, the casing sections 12and 13 are provided with intertting side walls 19 and 21, here ofrectilinear form, which are slidably engaged with each other to permitvertical telescopic movement between the sections, while maintaining asubstantially sealed condition of the chamber 14.

As here shown, the lower casing section 13 is formed with a horizontalbottom wall 23 having an opening 24 formed therein in registry with therotary grooving means 16 to permit extension of the latter therethroughand into cutting engagement with the step 1'7 upon the above describedtelescopic movement of said sections. A plurality of rollers 22 arejournalled to the section 13 and protrude through the bottom wall 23 andinto supporting engagement with the step 17 to facilitate movement ofthe machine thereover. As may best be seen in Figure 2 of the drawing,the upper casing section 12 is proportioned so that its side wall 19encompasses the lower section side wall 21, and is provided with anintegral top plate or horizontal top wall 26 from which the side wall-19depends.

The rotary grooving means 16 preferably consists of one or more circularcutting disks, here provided in the form of grinding wheels 27, 28 and29, which are mounted in parallel spaced arrangement on a shaft 31extending across the chamber 14 and journalled in bearings 32 and 33secured to the external sides of opposed portions 34 and 36 of the sidewall 19. As may be seen in Figures 2 and 4, the lower casing side wall21 extends upwardly past the shaft 31 and suitable slots 37 are providedin the wall 21 to accommodate the relative movement of the shaft upontelescoping movement of the sections. The grinding wheels 27, 28 and 29are secured to the shaft for rotation therewith and as here shown, a nut38 is engaged with a threaded portion 39 of the shaft 31 yand bearsagainst a washer 41 abutting the outer side of the grinding wheel 27.Any desired spacing of the grinding wheels axially along the shaft 31 isaccomplished by the provision of spacer sleeves 42 and 43 of the desiredlength mounted on the shaft between adjacent grinding wheels. Securingof the grinding wheels to the shaft is effected by clamping the wheelsand spacer sleevesy between the nut 38 and a suitable collar 44 formedon the shaft 31 in abutting engagement with the outer side of thegrinding wheel l29. If desired, the grinding wheels may be additionallyheld against rotational slipping on the shaft by splining or keying thewheel hubs to the shaft.

Motor means for driving the shaft 31 and associated grinding wheels ishere provided by an electric motor 4'7 carried on the top plate 26 ofthe upper housing section 12 and having its drive shaft connected bypulley 48 and belts 49 to a pulley 51 on the end of shaft 31. As will benoted, the motor 47 and the grinding means 16 are both carried by andsupported on the upper casing section 12 and are movable upwardly anddownwardly therewith as a unit, that is, with the motor and drive shaftat a constant spacing from each other. Take-up of any slack in the beltwhich may be caused by stretching or the like under long use is hereconveniently effected by securing the motor to overhanging portions 52and 53 of the top plate 26 by means of bolts 54 passing through slots 56and 57 formed in the top plate overhang at right angles to the shaft 31.In this manner, take-up of any slack in the belt 49 may be effected bymerely loosening the bolts S4 and sliding the motor along the slots 56and 57 until the slack is eliminated, whereupon the bolts may beretightened to hold the motor securely to the plate 26.

As an important feature of the invention, the above noted means 18 foraccomplishing the telescoping displacement of the casing sections 12 and13 is adapted to provide a straight up and down movement of the uppersection 12, whereby the telescoping action is obtained without relativecocking or binding between the sections. in accordance with the presentinvention, the means 18 includes a plurality of vertically oriented andhorizontally spaced screw members Sti, 59, 61 and 6?., which provide athreaded connection between the sections and which are jointly operableto provide the above described uniform telescoping displacement betweenthe sections. The screw members are arranged in substantially evenlyspaced positions along the side walls 19 and 21 to provide asubstantially uniform weight distribution on each of the screw members.As here shown, the screw members 5S and 59, 6i) and 6l are preferablymounted adjacent the corners 63, 64, 66, and 67 of the casing 11. Eachof the screw members is journalled for rotation in the top plate 26 andis held against axial displacement relative thereto by a pair ofconfronting shoulders 68 and 69 provided on the screws on opposite sidesof the plate 26. The screws extend downwardly through the chamber 14 andinto threaded engagement with nut members 71, 72, 73 and 74- attached tothe lower casing section side wall 21. the same pitch and, accordingly,a simultaneous equal rotation of' the screws will serve to raise andlower each portion of the upper section 12 by the same amount relativeto the lower section 13.

Means is provided for interconnecting the screw members 53 and 59, 61and 62 for the above described simultaneous equal rotation. As hereshown, this means comprises a continuous roller chain 77 engaged aroundsprockets 78, 79, 81 and 32 secured to the upper ends of the screwmembers 55, 59, 61 and 62 respectively, externally of the plate 26. Inthis connection it will be noted that the sprockets many convenientlyprovide the shoulders 68 While the shoulders 69 may be provided bycollars 70 formed on the screw members. Means for driving the rollerchain 77 to effect simultaneous rotation of the screw members hereconsists of a manually engageabie crani; 83 secured to an upwardextension 84 of one of the screw members, here screw member 59.

The above described structure of the casing 11 is designed to achieve amore efiicient removal of dust and grit from the grinding wheels toprevent contaminating the air and dirtying the surrounding area. Asshown in Figures l, 2 and 3 an opening 86 is formed in the top plate 26and is surrounded by an upwardly extending member 87 adapted forconnection to a hose 8S, leading to a suitable vacuum device (notshown). This vacuum device may be of any suitable form and good resultscan be achieved by the use of a centrifugal dust separator or even by aconventional vacuum cleaner. As will be noted from Figures 2 and 4 ofthe drawing, the opening 24 provided in the bottom wall 23 is onlyslightly larger than is necessary for passing the grinding wheels intotheir desired cutting engagement with the step 17. Also the bottom wall23 of the casing is supported by the rollers 22 relatively close to thestep 17 so that a confined passage 9i) is provided under the wall 23leading to the suction opening 24 and around the grinding wheels throughwhich air is rapidly drawn to most effectively remove the grit and dustgenerated by the grinding action.

The threads on all of the screws are of Another feature of the presentdevice is the provision of improved guide means for use with thegrooving machine when cutting grooves along the edge of a step, theguide means functioning to engage the edge of the step being grooved andto thereby precisely determine the positioning of the grooves on thestep. As here shown, such means includes a pair of elongated members 91and 92 slidably mounted for horizontal reciprocation through oppositeportions 93 and -94 of the lower casing section side wall 21, see Figure4. The members 91 and 92 are arvranged in spaced parallel relation toeach other and preferably pass through the lower casing section adjacentits opposite ends, as shown in Figures 3 and 4. 'l he members 91 and 92are valso arranged in parallel relation to the shaft 31 and extend tothe outside of the casing section 13 on the same side as the drive belts49. An elongated guide member 96, here a length of angle iron, isaffixed to the outer ends 97 and 98 of members 91 and 92 which, as maybe seen in Figure 2, are bent in a U-shape so as to position the guidemember 96 below the bottom Wall 23 and rollers 22 in position forsliding engagement with the edge or vertical face 99 of the step 17.Setscrews 101 and 102 carried by sidewall 2l and bearing upon members 91and 92 afford convenient means for adjustably fixing the tion` of guidemember 96 for controlling the location of the cutting wheels on thestep.

ln operation the machine is positioned on the step or other surface tobe grooved. Where grooves are to be cut in the tread of a step parallelto the edge of the step in the manner illustrated in Figure 2 of thedrawing, the guide 96 is adjusted so as to locate the cutter Wheels 27,28 and 29 at the desired location on the top surface of the step. Thesuction hose 88 is connected to the fitting 87 and to a suitable vacuumsource. The electric motor 47 is then energized and the crank 83 rotatedso as to lower the grinding wheels through the open bottom of the casingand into Contact with the surface of the step and to a depth into suchsurface desired for a first pass over the surface. The machine may thenbe easily moved by hand across the surface on the rollers 22 with theguide 95 Vmaintained in contact with the face 99 of the step. Uponcompletion of the pass in one direction, lengthwise of the step, thecrank may be rotated to further lower the rollers for a second pass.Several passes may thus be successively taken to obtain a desired depthof the groove. Meanwhile all of the grit and dust generated by thegrinding operation is rapidly sucked away from the grinding area andthrough the chamber 14 and into the suction hose 88. The machine may beused for grooving all types of material into which the grinding wheelswill cut when the machine is operated in the manner outlined above, andis especially effective on materials of the type commonly used in stepsand flooring and including cement, terrazzo, marble, and the like. Afterforming of the grooves, as above described, they may be filled with asuitable friction non-slip material of a character providing goodtraction under foot or, alternatively, a material of contrasting coloror texture to provide an ornamental and decorative effect.

I claim:

l. A grooving machine of the character described comprising, a casingadapted for positioning upon and for movement over a surface to begrooved and composed of upper and lower telescoping sections having sidewalls slidably engaged to define a vertically extensible charrn beropening at its bottom to said surface, rotary grooving means carried bysaid upper section and movable therewith upon relative telescopingmovement of said sections through the bottom of said chamber and intocutting engagement with said surface, means carried by said casing forconnection to a suction device for evacuating said chamber, and manuallyoperable means for effecting relative telescoping movement of saidsections to control the depth of cut of said disk in saidsurface.

2. A grooving machine of the character described comprising, a easingadapted for positioning on a `surface to be avoasve grooved and composedof upper and lower telescoping sections having side Walls slidablyengaged to define a vertically extensible chamber opening at its bottomt'o said surface, rollers carried at the lower end of said lower sectionfor supporting engagement with said surface to facilitate movement ofsaid machine thereover, a cutting disk journalled for rot'ation by saidupper section in position for extending through the bottom of saidchamber for cutting engagement with said surface, a motor carried onsaid upper section and connected to said disk for rotation thereof,means carried by said casing for connection to a suction device forevacuating said chamber, and manually operable means for effectingrelative displacement of said sections to control the depth of cut ofsaid disk in said surface.

3. A grooving machine of the character described comprising, a casingincluding an upper section having a top wall and depending side wall anda lower section having a bottom wall and upstanding side walltelescopically engaged with said depending side wall, rollers carried bysaid bottom wall for supporting said machine upon a surface to begrooved for movement thereover, a shaft carried by said depending sidewall within said casing, a motor carried by said top wall and connectedto said shaft for effecting rotation thereof, a cutting disk carried bysaid shaft, said bottom wall being formed with an opening inregistration with said cutting disk to permit extension of the lattertherethrough into cutting engagement with said surface upon telescopingdisplacement of said sections, and manually engageable means foreffecting said telescoping displacement.

4. A grooving machine comprising, a casing including an upper sectionhaving a top wall and depending rectangularly arranged side walls and alower section having a bottom wall and upstanding rectangularly arrangedside walls telescopically engaged with said depending side walls,rollers carried by said bottom Wall for supporting said machine upon asurface to be grooved for movement thereover, a shaft carried by saiddepending side Wall within said casing, a motor carried by said top walland con-- nected to said shaft for effecting rotation thereof, a cuttingdisk carried by said shaft, said bottom wall being formed with anopening in registration with said cutting disk to permit extension orthe latter therethrough into cutting engagement with said surface upontelescoping displacement of said sections, a plurality of verticallydisposed screw members positioned in the corners of said rectangulartelescopically engaged side walls and connecting said sections andarranged upon rotation to effect said telescoping displacement of saidsections, manually engageable means for rotating one of said screwmembers, and chain and sprocket means connecting said screw members forsimultaneous rotation.

5. A step grooving machine comprising, a casing adapted for positioningupon for movement over a step to be grooved and including an uppersection having a top wall and depending opposite side walls and a lowersection having a bottom wall and upstanding opposite side wallstelescopically engaged with said depending side walls to define avertically extensible chamber, a shaft supported for rotation uponoppositely related side walls of said upper section in horizontallyspanning relation across the interior of said chamber, a plurality ofcutting disks carried by said shaft in axially spaced relation thereonand for rotation therewith, a motor mounted on said upper wall andconnected to said shaft for effecting rotation thereof and said cuttingdisks, said bottom wall being formed with an opening in registrationwith said cutting disks to permit extension of the latter therethroughinto cutting engagement with said step upon telescoping displacement ofsaid sections, a plurality of screw members providing a threadedconnection between said sections for effecting upon rotation saidtelescoping displacement and being arranged in substantially evenlyspaced positions around said side walls, manually operable means forsimultaneously rotating said screw members, a pair of elongated membersslidably mounted for horizontal reciprocation through oppositely relatedside walls of said lower section and arranged in spaced parallelrelation and parallel to said shaft, a guide member fixed to outer endsof said elongated members in perpendicular relation thereto exteriorlyof one side of said casing and positioned be- 10W said bottom wall forengagement with an edge of said step, and means for fastening saidelongated members to said lower section in adjustable positions fordetermining the position of said disks for grooving the step at desireddistances from said step edge engaged by said guide members.

References Cited inthe tile of this patent UNITED STATES PATENTS'798,455 Schlueter Aug. 29, 1905 1,352,582 Clarke Sept. 14, 19201,356,338 Clarke Oct. 19, 1920 1,356,339 Clarke Oct. 19, 1920 1,687,998Wendig Oct. 16, 1928 1,736,538 Kurtz Nov. 19, 1929 1,845,666 JenningsFeb. 16, 1932 2,291,058 Pohl July 28, 1942

